基于镜检与DNA宏条形码技术的恰甫其海伊犁鲈食性特征研究OA

As an economically dominant fish species in tributaries and reservoirs of the Ili River Basin in Xinjiang,studying the feeding habits of Perca schrenkii is essential to clarify its prey and trophic level.We used a combination of microscopic examination and DNA metabarcoding to systematically analyze the feeding intensity,dietary composition,and seasonal variations of Perca schrenkii in Qiapuqihai Reservoir,Xinjiang.The results indicated that the annual feeding rate of Perca schrenkii reached 93%,with the highest feeding intensity observed in autumn,followed by spring;the lowest was observed in summer.Microscopic examination revealed that the diet primarily consisted of zooplankton(Daphnia and Sinocalanus)and benthic organisms(Chironomus),followed by fish(Abbottina rivularis and Carassius auratus gibelio).Microscopy complemented by DNA metabarcoding identified prey such as small fish and revealed eight additional genera of microorganisms,resulting in a 51.5%genus-level overlap and demonstrating significant methodological complementarity.Similarity analysis of prey organisms across seasons revealed significant differences in dietary composition(P<0.05).Non-metric multidimensional scaling results indicated distinguishable distributions of samples among seasons,with a richer prey diversity in spring and a relatively simpler composition in summer.The results of this study demonstrate that combining both methods significantly enhances prey identification comprehensiveness,thereby systematically revealing the ecological feeding characteristics of Perca schrenkii.These findings provide a theoretical foundation for understanding energy flow in the Qiapuqihai Reservoir aquatic ecosystem and managing fishery resources.